Lung And Laryngeal Cancers In Relation To Shipyard Employment In Coastal Virginia

Our plain-English summary of Lung And Laryngeal Cancers In Relation To Shipyard Employment In Coastal Virginia, by W.J. Blot, L.E. Morris, R. Stroube, et al (1980).

The study

• Authors: W.J. Blot, L.E. Morris, R. Stroube, I. Tagnon, J.F. Fraumeni, Jr
• Published: Journal Of The National Cancer Institute 65(3):571-575, September (1980)
• Type of article: Journal article
• Our copy: from Johns-Manville's own medical library, J-M no. 000790. The article is still under copyright, so we describe it here rather than post it.

In plain English

The authors interviewed relatives of deceased men from Tidewater (coastal) Virginia for a case-control study. The final groups were 336 men who died of lung cancer, 64 who died of laryngeal cancer, and 361 controls who died of other causes, not chronic lung disease. Men who began shipyard work before 1950 had a higher risk of lung cancer. After adjustment for race and smoking, the relative risk was 1.7 (95% confidence limits 1.2-2.4). The risk was similar for men who worked a few years, mostly during World War II, and for career shipyard workers. No increase was seen in men starting after 1949, though the authors noted too little time may have passed. Only a minority of shipyard workers were reported to have handled asbestos. For laryngeal cancer, there was no overall excess risk associated with shipyard employment. Among black men, the smoking-adjusted relative risk for pre-1950 shipyard work was 2.4 (1.0-5.9); among white men it was 0.23 (0.06-0.9). The authors concluded that 1940s shipyard work seems at least partly responsible for the raised respiratory cancer risk and that asbestos probably contributed.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Case-control study using interviews with next of kin of deceased men
• Who was studied: Male residents of Tidewater Virginia. Cases were deaths from lung cancer in 1976 and from laryngeal cancer in 1972-76. Controls died of other causes and were matched on race, age, year of death and residence. The final study group was 336 lung cancer patients, 64 larynx cancer patients and 361 controls.
• Exposure: Employment in the shipbuilding industry, analyzed as career or noncareer and by whether it began before or after 1950. Reported handling of asbestos was also examined. No fiber type is named.
• Main results:
  • Lung cancer: for shipyard work begun before 1950, the relative risk adjusted for race and cigarette smoking was 1.7, with approximate 95% confidence limits of 1.2-2.4
  • Lung cancer, among men first employed before 1950: the relative risk was 1.4 for career and 1.6 for noncareer shipyard employees, with no trend of rising risk with longer employment
  • Lung cancer by race, smoking-adjusted: relative risk 1.7 for whites (95% confidence limits 1.1-2.7) and 1.6 for blacks (0.8-3.2)
  • Lung cancer risk was not increased among the smaller number of men who began shipyard work after 1949
  • The largest excess lung cancer risk from shipyard work was among heavy smokers, which the authors said suggested a synergism between the two risk factors
  • Among shipyard workers, 18% of lung cancer patients and 23% of controls were reported to have handled asbestos. Among those not reported to have handled asbestos, the relative risk for shipyard work begun before 1950 was 2.0 (95% confidence limits 1.3-3.0).
  • Among men never employed in shipbuilding, 12% of lung cancer patients and 4.9% of controls reported asbestos exposure, typically in construction jobs. The adjusted relative risk was 2.2.
  • Laryngeal cancer: there was no overall excess risk associated with shipyard employment. 13 (20%) patients had worked in shipbuilding before 1950, compared with 21% of controls, and 11 of the 13 were black. Tidewater laryngeal cancer death rates did exceed U.S. rates.
  • Laryngeal cancer, smoking-adjusted relative risk for shipyard work begun before 1950: 2.4 among blacks (95% confidence limits 1.0-5.9) and 0.23 among whites (95% confidence limits 0.06-0.9)
  • Laryngeal cancer: the relative risk for alcohol consumption, adjusted for race and smoking, was 2.6 (95% confidence limits 1.1-6.2)
• The authors' conclusion: The authors concluded that asbestos probably contributed to the excess lung cancer among Virginia shipyard workers. They also concluded that Tidewater shipyard employment in the 1940s seems at least partly responsible for the increased respiratory cancer risk in the 1970s.
• Limitations the authors state:
  • Comparisons may have been affected by the lower response rate among controls, by publicity about asbestos and cancer, and by next-of-kin interviews that limited occupational detail
  • Second-party reporting and recall of events 30 or more years earlier may have caused inaccuracies
  • The small number of laryngeal cancer cases prevented further analysis of interactions between risk factors
  • For men who began work after 1949, not enough time may have passed for respiratory tumors to appear

Topics

Medical terms in this study, explained in our Lexicon: Laryngeal Cancer, Case-Control Study, Lung Cancer, Relative Risk.

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